The invention relates particularly, but not exclusively, to electromechanical force transducers of the kind described in International patent application WO01/54450 to the present applicant (incorporated herein by reference), and comprising one or more resonant elements or beams having a frequency distribution of modes in the operative frequency range of the transducer. Such transducers are known as “distributed mode actuators” or DMA for short.
It is an object of the invention to provide a transducer in which damping is provided to result in a reduction of Q of the modes and a reduction in the severity of cancellation between modes to give an increased smoothness of acoustic pressure.
It is also an object of the invention to improve the robustness of the transducer e.g. to give a reduction of chance of failure during drop or impact tests.
Another object of the invention is to reduce the first resonant mode frequency of an actuator or transducer, e.g. a DMA transducer.
Yet another object of the invention is to reduce the sensitivity of transducer performance to the properties of the panel to which it is attached.